1. Field of the Invention
The present invention relates to a novel cephalosporin derivative, a salt thereof, a process for the manufacture of same and a pharmaceutical agent comprising same.
2. Related Arts
A study on cephalosporins has been started from a separation of several antibiotics from a culture solution for Cephalosporium acremonium, which were given a name to Cephalosporin P.sub.1 to P.sub.5 and N, respectively. Thereafter, Cephalosporin C has been isolated from a crude Cephalosporin N.
This Cephalosporin C has a wide antibacterial spectrum to prevent the growth of Gram-positive and negative pathogens, but shows a drawback of a relatively low antibacterial power.
Therefore, various derivatives of the Cephalosporin C have been developped, in which acetoxymethyl radical in 3-position is substituted with another radical or D-.alpha.-aminoadipic acid radical bonded to amino radical in 7-position is substituted with another acid radical. As examplar compounds among the derivatives, there are Cephaloridine namely 7-(2-thienyl)acetamido-3-pyridin-1-yl-methyl-3-cephem-4-carboxylate (U.S. Pat. No. 3,449,338), Cephotaxim namely sodium 7-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-acetoxymethyl-3-ceph em-4-carboxylate (U.S. Pat. No. 4,152,432) and the like.
Each of the Cephalosporin C derivatives has the antibacterial spectrum wider than that of penicillins, is effective also to infectious diseases due to Gram-negative pathogens, can be dosed to patients with a penicillin hyperergy due to its low cross allergie to penicillins, and show a relatively low crossed tolerance to penicillins. Therfore, some of those inclusive of said Cephaloridine have already hold a remarkable position in crinical view points.
In order to further develop antibiotical therapy by cephalosporin compounds, however, those having more wide antibacterial spectrum and showing more high activity to fast bacterias and more particularly to Gram-negative pathogens have highly been demanded.